Q30.A hydrogen atom changes its state from n = 3 to n = 2. Due to recoil, the percentage change in the wave length of emitted light is approximately 1 × 10−n . The value of n is_____. [Given Rhc = 13.6eV, hc = 1242eVnm, h = 6.6 × 10−34 J s mass of the hydrogenatom = 1.6 × 10−27 kg ] JEE Main 2024 (04 Apr Shift 1) JEE Main Previous Year Paper
What This Question Tests
This question involves calculating the energy of an emitted photon, then determining the recoil kinetic energy of the atom due to momentum conservation, and finally finding the percentage change in wavelength.
Concepts Tested
Formulas Used
E = Rhc(1/n₂² - 1/n₁²)
p = E/c
p_recoil = p_photon
K_recoil = p²/2m
ΔE = K_recoil
📚 NCERT Sections This Tests
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
11.4 — Monochromatic Light Of Wavelength 632.8 Nm Is Produced By A
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11.4 Monochromatic light of wavelength 632.8 nm is produced by a helium-neon laser. The power emitted is 9.42 mW. (a) Find the energy and momentum of each photon in the light beam, (b) How many photons per second, on the average, arrive at a target irradiated by this beam? (Assume the beam to have uniform cross-section which is less than the target area), and (c) How fast does a hydrogen atom have to travel in order to have the same momentum as that of the photon?
12.4 — The Ground State Energy Of Hydrogen Atom Is –13.6 Ev. What Are The
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12.4 The ground state energy of hydrogen atom is –13.6 eV. What are the kinetic and potential energies of the electron in this state?
📋 Question Details
- Chapter
- Atoms
- Topic
- Atomic spectra and recoil energy
- Year
- 2024
- Shift
- 04 Apr Shift 1
- Q Number
- Q30
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 12: Atoms
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